{"doi":"10.1002/cbic.201900318","title":"Protein Spin Labeling with a Photocaged Nitroxide Using Diels–Alder Chemistry","abstract":"<jats:title>Abstract</jats:title>\n                  <jats:p>\n                    EPR spectroscopy of diamagnetic bio‐macromolecules is based on site‐directed spin labeling (SDSL). Herein, a novel labeling strategy for proteins is presented. A nitroxide‐based spin label has been developed and synthesized that can be ligated to proteins by an inverse‐electron‐demand Diels–Alder (DA\n                    <jats:sub>inv</jats:sub>\n                    ) cycloaddition to genetically encoded noncanonical amino acids. The nitroxide moiety is shielded by a photoremovable protecting group with an attached tetra(ethylene glycol) unit to achieve water solubility. SDSL is demonstrated on two model proteins with the photoactivatable nitroxide for DA\n                    <jats:sub>inv</jats:sub>\n                    reaction (PaNDA) label. The strategy features high reaction rates, combined with high selectivity, and the possibility to deprotect the nitroxide in\n                    <jats:italic>Escherichia coli</jats:italic>\n                    lysate.\n                  </jats:p>","journal":"ChemBioChem","year":2019,"id":658174,"datarank":0.8460471926851788,"base_score":3.2188758248682006,"endowment":3.2188758248682006,"self_citation_contribution":0.48283137373023016,"citation_network_contribution":0.36321581895494864,"self_endowment_contribution":0.48283137373023016,"citer_contribution":0.36321581895494864,"corpus_percentile":null,"corpus_rank":null,"citation_count":24,"citer_count":16,"citers_with_citation_signal":15,"citers_with_endowment":15,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1718101,"name":"Bjarne Silkenath","orcid":"0000-0001-9862-6076","position":1,"is_corresponding":false},{"id":1718102,"name":"Jakob Langer","orcid":"0000-0002-0095-1936","position":2,"is_corresponding":false},{"id":1718103,"name":"Valentin Wittmann","orcid":"0000-0003-4043-6813","position":3,"is_corresponding":false},{"id":1718104,"name":"Malte Drescher","orcid":"0000-0002-3571-3452","position":4,"is_corresponding":false},{"id":1718100,"name":"Anandi Kugele","orcid":"0000-0002-1016-8910","position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Protein Spin Labeling with a Photocaged Nitroxide Using Diels–Alder Chemistry","abstract":"<jats:title>Abstract</jats:title>\n                  <jats:p>\n                    EPR spectroscopy of diamagnetic bio‐macromolecules is based on site‐directed spin labeling (SDSL). Herein, a novel labeling strategy for proteins is presented. A nitroxide‐based spin label has been developed and synthesized that can be ligated to proteins by an inverse‐electron‐demand Diels–Alder (DA\n                    <jats:sub>inv</jats:sub>\n                    ) cycloaddition to genetically encoded noncanonical amino acids. The nitroxide moiety is shielded by a photoremovable protecting group with an attached tetra(ethylene glycol) unit to achieve water solubility. SDSL is demonstrated on two model proteins with the photoactivatable nitroxide for DA\n                    <jats:sub>inv</jats:sub>\n                    reaction (PaNDA) label. The strategy features high reaction rates, combined with high selectivity, and the possibility to deprotect the nitroxide in\n                    <jats:italic>Escherichia coli</jats:italic>\n                    lysate.\n                  </jats:p>","is_dataset_classified":null,"base_score":3.2188758248682006,"endowment":3.2188758248682006,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"31090999","pmcid":"PMC6790680","openalex_id":"https://openalex.org/W2945226961","authors":[],"funders":[{"funder_name":"H2020 European Research Council","grant_id":"772027 - SPICE - ERC-2017-COG","title":null},{"funder_name":"Deutsche Forschungsgemeinschaft","grant_id":"SFB 969, Project C3","title":null},{"funder_name":"Deutsche Forschungsgemeinschaft","grant_id":"SFB 969, Project B5","title":null},{"funder_name":"European Research Council","grant_id":"772027","title":"Spectroscopy in cells \nwith tailored in-vivo labelling strategies \nand multiply addressable nano-structural probes"},{"funder_name":"Deutsche Forschungsgemeinschaft","grant_id":"unidentified","title":"unidentified"},{"funder_name":"Deutsche Forschungsgemeinschaft","grant_id":"189682160/SFB 969","title":"Chemical and biological principles of cellular proteostasis"}],"total_grants":6,"fwci":3.3156,"citation_percentile":0.91913595,"influential_citations":0,"citation_trend":[{"year":2019,"count":5},{"year":2020,"count":3},{"year":2021,"count":4},{"year":2022,"count":3},{"year":2023,"count":6},{"year":2024,"count":3}],"oa_status":"hybrid","license":"cc-by","oa_locations":[{"url":"https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/cbic.201900318","host_type":"journal"},{"url":"https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/cbic.201900318","host_type":"publisher"},{"url":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fcbic.201900318","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1002/cbic.201900318","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/full-xml/10.1002/cbic.201900318","host_type":"publisher"},{"url":"https://chemistry-europe.onlinelibrary.wiley.com/doi/pdf/10.1002/cbic.201900318","host_type":"publisher"},{"url":"https://doi.org/10.1002/cbic.201900318","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/31090999","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/6790680","host_type":"repository"},{"url":"http://nbn-resolving.de/urn:nbn:de:bsz:352-2-68onpzy40sdh1","host_type":"repository"},{"url":"https://europepmc.org/articles/PMC6790680","host_type":"Europe_PMC"},{"url":"https://europepmc.org/articles/PMC6790680?pdf=render","host_type":"Europe_PMC"},{"url":"https://doi.org/10.26434/chemrxiv.7931192.v1","host_type":""},{"url":"https://kops.uni-konstanz.de/bitstream/123456789/46050/1/Kugele_2-68onpzy40sdh1.pdf","host_type":""},{"url":"http://dx.doi.org/10.1002/cbic.201900318","host_type":""},{"url":"https://dx.doi.org/10.1002/cbic.201900318","host_type":""}],"fields_of_study":["Electron Spin Resonance Studies","Lanthanide and Transition Metal Complexes","Hemoglobin structure and function","01 natural sciences","0104 chemical sciences","Amino Acids","Cycloaddition Reaction","Electron Spin Resonance Spectroscopy","Humans","Nitrogen Oxides","Proteins","Spin Labels"],"mesh_terms":["Amino Acids","Electron Spin Resonance Spectroscopy","Humans","Nitrogen Oxides","Proteins","Spin Labels","Cycloaddition Reaction"],"keywords":["Nitroxide mediated radical polymerization","Chemistry","Site-directed spin labeling","Diels–Alder reaction","Click chemistry","Biophysics","Computational chemistry","Organic chemistry","Biochemistry","Biology","Polymerization","Polymer","Radical polymerization","Cycloaddition","Epr Spectroscopy","Bioorthogonal Chemistry","Noncanonical Amino Acids","info:eu-repo/classification/ddc/540","Cycloaddition Reaction","EPR spectroscopy, Cycloaddition, Bioorthogonal chemistry, non-canonical amino acids, Site-directed spin labeling","Electron Spin Resonance Spectroscopy","Humans","Proteins","Nitrogen Oxides","Spin Labels","Amino Acids","Communications"],"sdg_mappings":[{"sdg_number":3,"sdg_label":"3. 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